The present invention relates to a device for cleaning a corona wire of a corona discharger which is installed in an electrophotographic copier, electrostatic printer or similar electrostatic recorder to serve as a charger or discharger.
A charger or a discharger for us in an electrostatic recorder of the kind described for charging a photoconductive element, transferring a toner image, expelling a charge or similar purpose is in many case implemented by a corona discharger. A corona discharge includes a trough-like shield member extending over the entire width of a photoconductive element, dielectric and blocks mounted on opposite ends of the shield member, and a tungsten wire or similar hairline stretched between the end blocks. When a high voltage is applied to the hairline, the hairline produces a corona discharge to thereby charge or discharge the surface of the photoconductive element. Such a hairline is usually referred to as a corona wire.
Various impurities such as particles of dust, toner and paper float in the interior of an electrostatic recorder of the above-described kind. As the recorder repeats its image forming operation, the impurities are sequentially deposited on the corona wire to lower the discharging efficiency and cause an irregular discharge distribution, lowering the quality recording. It has been customary for the corona discharger to be removed from a recorder body and cleaned by a serviceman at certain intervals, at the sacrifice of cost.
An implementation recently proposed to eliminate the above problem is a cleaning member which is movable along the corona wire and is moved along the latter periodically to remove toner, paper dust and other impurities. Such a cleaning member is retained by an exclusive support member which is in many cases driven by a drive wire and pulleys. However, since ozone is produced in the corona discharger due to corona discharges and since the temperature inside a copier is high due to various kinds of heat sources, the drive wire and pulleys are easy to deteriorate and/or to deform (e.g. elongation of the belt) and fail in a short period of time. With this kind of cleaning member, therefore, it is impossible to clean the corona discharger with stability.